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Re: percentage?

Originally Posted by sky753

Hello Everyone,

The following is taken from BSH glass printing requirements. One sentenc I am totally confusted. Hope you can offer your replies here!

All dots of the imprint must be in place.10 % of the dots may have ± 25 % of the target print area.5 % of the dots may have up to 50 % of the target print area,accumulated on a maximum area of 50 x 50 mm.

What does the underlined mean here?

This is a specification of the quality of the printing. Look closely at a black and white newspaper photograph (a 'half-tone') and you'll see thousands of little dots. If the picture meets a specified quality, the size of the dot - near enough, within the tolerance of the spec. - is the same as 'the target print area'. Lots of big dots trick the human eye into seeing that part of the picture as black.

In your case, 85% of the dots must be at or very close to the target print area. 10% of them can be between 75% and 125% of the target area. And 5% of them can have between 50% and 150% of the target print area. (I'm guessing here, but I think there's a "±" missing). And this quality standard must be maintained throughout a square 50mm X 50mm (that is, a big picture doesn't meet the spec. if most of it is perfect but a square that small is substandard).

I don't know how this would translate to glass printing, but presumably the principles are the same.